1. Field of the Invention
The present invention relates, in general, to one-piece apertured fasteners which are fixedly mountable on a shaft, stud, pin or the like to attach a mechanical element to the shaft.
2. Description of the Art
A variety of one-piece apertured fasteners which are fixedly mountable over a cylindrical shaft, stud or pin to attach a mechanical element, such as a metal sheet or panel, to the shaft are well known. In one type of fastener, an aperture is pierced or punched in a metal sheet and notches are formed in the portion of the sheet surrounding the aperture to form projections which engage a shaft or stud forced through the aperture to mount the fastener on the shaft or stud.
In another common fastener of this type, a frusto-conical annulus is formed in a generally annular blank and simultaneously an aperture is formed centrally in the annulus. The edge of the annulus surrounding the aperture forms a shaft engaging edge.
Such fasteners are used in a variety of applications to join a mechanical element, such as a panel, sheet, etc., to a shaft, stud or pin. In certain applications, the shaft is nickel plated for long life, high strength, etc. However, the use of nickel plating creates problems relating to the increased cost of providing environmentally safe plating operations, difficulties in forming a constant uniform thickness of the nickel plate on the shaft, and the occurrence of scratches through the nickel plating on the shaft when the fastener is forced over a shaft or stud, and the high cost of the plating operation itself. As a result, it is clear that other fastening techniques without these deficiencies are needed. Thus, it would be desirable to provide a fastener which retains a mechanical element to a shaft which eliminates the need for plating of the shaft to provide anti-corrosion properties.